Replace vSphere, vCenter, vSAN, NSX, and the rest of VCF with one Kubernetes-native platform on your own bare metal — no per-CPU licensing, no Broadcom renewal cliff, no US-vendor lock-in.
Cozystack is a CNCF Sandbox project. Ænix created it, co-maintains it with maintainers from other companies, runs it in production with hosting providers, and runs the migration end to end.
Pairs with: Ænix Public Cloud Platform for anyone selling cloud — hosting providers exiting VMware Cloud Director, MSPs, telcos, national operators; Ænix Private Cloud Platform for regulated enterprises exiting VMware Cloud Foundation. Service providers exiting VMware Cloud Director: see the VCD alternative. Free VMware Migration Checklist →.
Where Cozystack fits in the VMware-alternative market
| Vendor | Stack model | Best for |
|---|---|---|
| Cozystack | Open-source, Kubernetes-native, multi-tenant | Service providers, regulated enterprises, sovereign cloud |
| Nutanix AHV | Proprietary HCI on certified nodes | VM-centric enterprise estates wanting one vendor |
| Proxmox VE | Open-source KVM/LXC | SMB and labs |
| Scale Computing HC3 | Appliance HCI | ROBO/edge |
| OpenShift Virtualization | KubeVirt + OpenShift licensing | Existing Red Hat customers |
| OpenStack | Mature open-source IaaS | Teams with dedicated platform engineering |
| Azure Local (formerly Azure Stack HCI) | Microsoft-licensed Hyper-V, Arc-managed | Microsoft-aligned shops |
For the wider market: Best VMware alternatives 2026 — market comparison. For a feature-by-feature view: Cozystack vs VMware — head to head.
Why teams replace VMware in 2026
1. Subscription-only economics, post-Broadcom Perpetual licences retired, mandatory VCF bundling, renewals subscription-only.
2. Stack-wide vendor lock-in vSphere, NSX, vSAN, vCD, Aria — replacing one means rebuilding the rest.
3. Sovereignty and regulator pressure DORA, NIS2, and on-prem mandates make a closed US hypervisor a documented operational risk.
4. Open-source velocity has overtaken VMware’s roadmap KubeVirt, Cilium, LINSTOR, and Flux ship faster as community projects than Broadcom can match in the open.
What Cozystack gives you instead
- Virtual machines — KubeVirt, KVM-based, live migration, snapshots
- Tenant Kubernetes — every tenant gets their own real K8s cluster
- Managed databases — PostgreSQL, MariaDB, Valkey, RabbitMQ, Kafka, ClickHouse, OpenSearch, MongoDB
- S3-compatible object storage — for backups, AI training data, applications
- GPU as a service — NVIDIA data-centre GPUs through the NVIDIA GPU Operator: passthrough of whole GPUs or NVIDIA vGPU for VMs (requires your NVIDIA vGPU licence), MIG partitions or time-sliced sharing via HAMi for pods
- Multi-tenant control plane — Tenant CRD, nested tenants, per-tenant quotas
- Observability — VictoriaMetrics + VictoriaLogs + Grafana, included
- Backup & DR — Velero to S3 outside the cluster, per-database PITR, DRBD replication; VM recovery as a documented runbook
- Self-service portal — Cozystack Dashboard; WHMCS billing integration is a proprietary Ænix module in Ænix Public Cloud Platform
Runs on your bare metal — no public-cloud dependency.
Where VMware is still the better choice
A comparison that only lists our wins is a battle card, not an evaluation. These are the places VMware is genuinely ahead, and they are the ones your architects will raise:
- Operational depth. DRS and Storage DRS, Fault Tolerance, Storage vMotion between arrays, vVols, EVC. KubeVirt live-migrates VMs and schedules them well; it does not match twenty years of automated placement and rebalancing behaviour.
- A certified hardware compatibility list. VMware qualifies servers, HBAs, NICs and firmware levels, and supports you on a listed configuration. Cozystack runs on commodity hardware, which means that qualification becomes yours.
- The backup and DR ecosystem. Veeam, Commvault, Rubrik, Zerto and Site Recovery Manager speak VADP natively. Velero plus per-database PITR covers backup and restore with different tools and no orchestrated failover, and every runbook, retention policy and piece of audit evidence built on the VMware ecosystem gets rewritten.
- ISV certification. Some application vendors certify only against ESXi and will decline a support call about the same workload on KubeVirt, whatever the technical merits.
- Windows guests with hard edges. VMs using Measured Boot do not convert, and Windows Server 2012 and 2012 R2 do not boot after conversion. Those are rebuilds, not migrations — see the VMware migration hub.
If your renewal is tolerable, your team is deep on vSphere, and no sovereignty or multi-tenancy requirement is pushing, staying is the right call and we will say so on the review.
VMware → Cozystack: one-to-one component mapping
| VMware / VCF | Cozystack equivalent |
|---|---|
| vSphere / ESXi | KubeVirt on Talos |
| vCenter | Kubernetes API + Cozystack Dashboard |
| vSAN | LINSTOR or SeaweedFS |
| NSX | Cilium (eBPF) |
| vCloud Director | Tenant CRD + Cozystack Dashboard |
| vRealize / Aria Operations | VictoriaMetrics + VictoriaLogs + Grafana |
| Site Recovery Manager | Velero + DRBD/stretched clusters + runbook (no automated orchestrated failover — see DR) |
| Tanzu Kubernetes Grid | Tenant Kubernetes (native) |
| vRealize Automation | Self-service service catalogue in the portal |
| VMware Cloud Foundation | Cozystack |
Two layers need redesign rather than 1:1 mapping: networking (Cilium ≠ NSX) and multi-tenancy (Tenant CRD ≠ vCD orgs). Both are addressed in the Platform Readiness Assessment.
Migration path — six steps
Discover
vSphere/VCF inventory, dependencies, workload buckets.
Deploy in parallel
Cozystack on new or repurposed hardware.
Migrate VMs
Konveyor Forklift drives virt-v2v and CDI; VirtIO injection and VMware Tools removal are automated.
Cut over networking and storage
Cilium policy parity, LINSTOR (DRBD) import.
Validate and cut over DR
Backup and restore with Velero plus rehearsed runbooks; there is no SRM-style orchestrated cross-site failover.
Decommission VMware
Repurpose hardware as VMware subscriptions lapse.
OpenStack, CloudStack, and Proxmox migrations follow the same playbook with different image-import and network-mapping steps.
Multi-tenancy and sovereignty
- Tenant CRD — each tenant is a Kubernetes-native isolation boundary, with quotas, RBAC, billing scope, and observability scope
- Nested tenants — for resellers and BU separation
- Air-gapped install — supported, documented, no extra licensing
- No phone-home telemetry — opt-in, disabled by default
- Built to support DORA / NIS2 work — operational resilience, supplier-risk transparency
- Support model — support works through your GitOps repository and, with your approval, remote access to your clusters
Cozystack vs VMware — at a glance
| VMware (VCF, post-Broadcom) | Cozystack + Ænix | |
|---|---|---|
| Licence model | Subscription only (VCF bundles) | Apache 2.0 + optional Ænix support subscription |
| Renewal risk | 2–5× increases seen in Ænix engagements | Predictable; OSS code remains usable regardless |
| Compute | vSphere / ESXi | KubeVirt (KVM-based) |
| Storage | vSAN | LINSTOR/DRBD (block), SeaweedFS (object) |
| Network | NSX | Cilium (eBPF, CNCF Graduated) |
| Multi-tenancy | vCloud Director | Tenant CRD (Kubernetes-native) |
| Backup / DR | Site Recovery Manager | Velero + DRBD/stretched clusters + runbook (no automated orchestrated failover — see DR) |
| Observability | vRealize / Aria (separate licence) | VictoriaMetrics + VictoriaLogs (included) |
| GPU for VMs | NVIDIA vGPU on vSphere | Passthrough or NVIDIA vGPU on KubeVirt (your NVIDIA vGPU licence) |
| Sovereignty | Closed source, US vendor | Open source, on-prem; EU contracts via AENIX s.r.o. |
| Air-gap install | Supported (extra licensing) | Supported (no extra cost) |
| Pricing transparency | Quote-driven, non-public | Public on aenix.io/pricing; OSS is free |
Companies running platforms built with Ænix
Hosting providers running Ænix Public Cloud Platform in production.
Hosting providers running Ænix Public Cloud Platform in production
"Running Nuvolos on sovereign bare metal meant we needed hyperscaler-grade multi-tenancy without the hyperscaler. Cozystack delivered exactly that — isolated tenants, shared GPUs, KubeVirt for legacy workloads — and it's why we can promise our customers infrastructure control, not just a workspace."
Alexandru PopescuCEO, Nuvolos
Written-up deployments, including a bank and a financial group, are in the case studies.
Pricing
Cozystack is open source and free to run.
- Regulated enterprises exiting VCF go through Ænix Private Cloud Platform, quoted per RFP after a Platform Readiness Assessment.
- Service providers on Ænix Public Cloud Platform and teams running Cozystack themselves buy support tiers per 10 physical nodes per month: Basic $1,250, Standard $3,000, Plus $5,500, Enterprise per RFP.
Migration services are scoped separately. Full breakdown on the pricing page. No per-CPU, per-VM, or per-core meter.
More questions about Windows VMs, vCD migration, hardware reuse, GPU support, and migration timelines: see the full VMware replacement guide on our blog or talk to us.
Running infrastructure and weighing the exit? See the guide for heads of infrastructure.
Three ways to start
Architecture call (30 min) Free. Your stack against the Cozystack mapping, with the obvious workload buckets and risk flags.
Platform Readiness Assessment (fixed price) 14 days (focused) or 28 days (full): inventory, dependencies, and a migration plan with timeline, budget and success criteria.
Production pilot Run a workload cohort on Cozystack hardware we provision, parallel to your VMware estate, validated against your application owners.
Or read the full VMware replacement guide on our blog · See the VMware migration path · Best VMware alternatives 2026 — market comparison · Cozystack vs VMware — head to head.
Cozystack is a CNCF Sandbox project, a CNCF Certified Kubernetes distribution, accepted into the CNCF Kubernetes AI Conformance program (September 2026), with an OpenSSF Best Practices badge. Ænix created Cozystack and co-maintains it.